There are two kinds of memory types; short term memory and long term memory. They are structurally and functionally different from each other.
Long term memory loss
Long term memories last for years or even decades. Short term memories move into long term memories through long term potentiation, which is the process of strengtening the connections between existing neurons.Either traumatic brain injury or neorodegenerative disease causes serious loss of long term memory.
Traumatic brain injury: When some parts of the brain have been damaged, the ability to remember tastes, smells, appearances, or sounds might be affected, depending on what part of it has been affected. If the brain swells because of a head injury, brain’s ability to process incoming information lessens. Moreover, retrieving the information when needed might be difficult, even if the incoming information is processed. You suffer from retrograde amnesia, When you suffer from traumatic injury to the head and forget where you had been or what you had been doing for a few days before the accident.
Neurodegenerative Disease: the most common neorodegenerative diseases are Alzheimer’s Disease, Dementia, Huntington’s Disease, Multiple Sclerosis and Parkinson’s Disease.These diseases cause memory loss.None of these conditions act specifically on memory, but memory deterioration is a casualty of general cognitive decline.
Short term memory loss
short term memory loss is scientifically called anterograde amnesia. In this case of amnesia, ?nformation stays in the short term memory and is not transferred to long term memory. If a person’s attention is shifted, he cannot remember events which have just broken out.different kinds of memory are affected differently.for example a person cannot remember the events which have just happened but can remember physical skills.
The cause of the short term memory loss is the damage to the hippocampus, fornix or mamilliary bodies.not only damage to this parts of the brain, but also to the basal forabrain causes short term memory loss. Peoeple who drink alcohol too much tend to have this disorder more.